Connector assembly with tine skewing housing

ABSTRACT

A new connector assembly provides improved electrical and mechanical contact between a pin of a circuit board and two connector forks that form part of the connector assembly. The assembly includes a plastic housing in which the tines of the two connector forks are skewed so that one of the two tines of each fork makes substantially full contact with one of two opposite sides of the pin and the other tine makes a cooperating partial contact on the other side. In the preferred connector assembly, the housing has two projections that each extend along one of two diagonally opposite edges of the pin and along the adjacent noncontact making sides of the pin so that the tines nearest the projections are held in substantially full contact with the pin. The other two tines are allowed to extend somewhat beyond the other edges of the pin. The housing is also able to hold a single contact fork. A single unskewed contact fork is approximately centered on the pin between the diagonally opposing projections of the housing.

[ June 27, 1972 [54] CONNECTOR ASSEMBLY WITH TINE SKEWING HOUSING [72] lnventors: Edmund J. Di Stefano; Arthur E. Ender- Iey, both of Poughkeepsie, NY.

International Business Machines Corporation, Armonk, NY.

[22] Filed: June 17,1970

[21] Appl.No.: 47,073

[73] Assignee:

[52] Cl. ..339/l4 R, 339/17 R, 339/65, 339/176 M ["11 I Int. (:1 ..H0lr 3/06 [58] Field OfSetll'Ch ..339/17, 19,65,66, 198,273, 339/176 M [56] References Cited UNITED STATES PATENTS 3,325,770 6/1967 Hammell et a1. ..339/l76 M 3,533,044 10/1970 Bauman et 31.... ..339/14 P 3,31 1,867 3/1967 Beauchaine ..339/217 l i i I l 1 1 y 1 /1 I r I l l I 1 I ri 5 l 12 1 'I 34 1 T 53 Ji l i5 340 3 350 I 40 350 L14 4 5 31 Q 36 u 380 u a 19 51b 35b 30 20 1 36 b Primary Examiner-Joseph H. McGlynn Assistant Examiner-Robert A. Hafer Attorney-Hanifin and Jancin and William S. Robertson ABSTRACT A new connector assembly provides improved electrical and mechanical contact between a pin of a circuit board and two a connector forks that form part of the connector assembly. The assembly includes a plastic housing in which the tines of the two connector forks are skewed so that one of the two tines of each fork makes substantially full contact with one of two opposite sides of the pin and the other tine makes a cooperating partial contact on the other side. In the preferred connector assembly, the housing has two projections that each extend along one of two diagonally opposite edges of the pin and along the adjacent non-contact making sides of the pin so that the tines nearest the projections are held in substantially full contact with the pin. The other two tines are allowed to extend somewhat beyond the other edges of the pin. The housing is also able to hold a single contact fork. A single unskewed contact fork is approximately centered on the pin between the diagonally opposing projections of the housing.

7 Claims, 5 Drawing Figures PATENTEnJuxzvmz INVENTORS ED .1. DI STEFANO AR E. ENDERLEY ATTORNEY CONNECTOR ASSEMBLY WITH TINE SKEWING HOUSING RELATED APPLICATIONS This application discloses an improvement that is particularly useful with the connector assembly of applications Ser. No. 737,644, filed June 17, 1968 now US. Pat. No. 3,533,044 and Ser. No. 858,476, filed Sept. 16, 1969 and assigned to the assignee of this invention.

INTRODUCTION A simplified description of the connector assembly of the related applications will give a helpful introduction to the terminology that will be used in this specification and to the objects of this invention, and it will also suggest variousother types of connector assemblies to which this invention applies. These connector assemblies are intended for use with a circuit board having rows of pins that project from one side of the board. A connector assembly includes either one or two electrical connector forks that each have a pair of tines which fit over a pin to make electrical and mechanical contact on two opposite sides of the pin. (The preferred connector assembly has other connector forks that do not fit on pins, but these will be specifically identified whenever they are referred to.) The connector forks are carried in a plastic housing that has a hole in its bottom wall that receives the pin and thereby aligns the connector assembly with the pin. For a connector assembly having a single connector fork, the sidewalls of the housing have been made as close as tolerances permit to the non-contact making sides of the pin so that the tines are held in alignment with the pin and cannot be inserted on the pin incorrectly or later slip off the pin.

For attaching two connector forks to one pin, the housing has been provided with a larger cavity for holding the two connector forks. Because the two connector forks together are wider than the pin, it has been particularly difficult to maintain good contact. At least one of the two connector forks must partially overhang the contact making sides of the pin and thereby make only partial contact. The sides of the housing must be spaced outward from the non-contact making sides of the pin, and with reasonable manufacturing tolerances the space between one of the walls and the pin may be large enough for a connector fork to fit into. Also, the walls of the housing may flex from their tine aligning position as the assembly is attached to a pin. Thus, the tines are liable to make an unsatisfactory, side to side, non-gripping contact with the pm.

One object of this invention is to provide a new and improved connector assembly having a housing that is useful for locating either one or two forked connectors on a pin. Another object of this invention is to provide a new and improved connector assembly in which a good electrical and mechanical contact is made between one or two connector forks and a pin through a wide range of manufacturing tolerances. A more specific object is to provide a new and improved connector housing for attaching a plurality of connector forks to a pin that is narrower than the plurality of forks.

THE INVENTION According to this invention, the tines of a connector fork are skewed so that one of the tines makes substantially full electrical contact and the other tine makes sufficient contact for the fork to grip the pin between the two tines.

In the preferred embodiment of the invention, a dielectric housing includes projections at two diagonally opposite edges of the pin that extend toward the adjacent tines sufiiciently, with respect to the tolerances to which the pin and the connector assembly are made, to prevent these tines from fitting between the pin and the side wall. The other two edges of the pin are unobstructed so that the other tines are free to extend over the edge of the pin. Preferably, the projections urge the adjacent tines to a position of substantially full electrical contact with the pin.

According to a more specific feature of the preferred connector assembly, the projections extend at least partly along the adjacent non-contact making sides of the pin and thereby help to align the housing with the pin.

Preferably, the connector fork is conventional with resillient tines that are not skewed except by the skewing action of the housing. Thus, the skewing action causes the tines that overhang the contact making sides of the pin to be urged sidewards toward fuller contact with the pin.

Other objects, advantages, and features of the invention will be apparent from the following detailed description of thepreferred embodiment of the invention.

THE DRAWING FIG. 1 is a simplified isometric of the connector of this invention.

FIG. 2 is a side view of the connector and an associated circuit board with parts removed.

FIG. 3 is a section along line 3-3 in FIG. 2.

FIG. 4 is a section along line 4-4 in FIG. 2.

FIG. 5 is a section along line 5-5.

THE PREFERRED CONNECTOR ASSEMBLY Conventional Features The isometric of FIG. 1 will help to explain the conventional features of the connector assembly and to show the relationship of the detailed views of the other figures. A non-conductive (plastic) housing for holding one or two independent connector forks has a sidewall 12 and an end wall 14. An opposite sidewall 13 is shown in each of the other figures, and an opposite end wall 15 is shown in FIGS. 2 and 5. The housing is open at the top for receiving two independent connector forks and is partially closed by a bottom wall 16 shown in FIG. 2. A tab 18 (explained in related application Ser. No. 858,476) formed as part of front wall 14 is shown also in FIG. 2, and a recess 19 for receiving a ground rail 30, (described later) is shown also in FIGS. 2 and 5. A connector fork retaining opening 20 in front wall 14 is shown also in FIG. 2.

The two connector forks are identical and interchangeable, and corresponding components are identified in the drawing by the same number with the suffix a for components of the connector fork shown to the right in FIG. 1 and the suffix b for components of the connector to the left. In this description, reference characters without the sufiix will be used wherever the components are referred to collectively or interchangeably.

As FIG. 1 shows, each connector has a non-conductive (plastic) coating 21 that supports a group of three wires 23 and the associated connector forks (not shown in FIG. 1). The center wire is a signal wire and the two outside wires are ground wires.

FIG. 2 shows additional conventional features of the connector assembly and of a circuit board 27 with which the connector assembly may be used. Circuit board 27 includes a strip of dielectric material 28 that helps to support a pin 29 and other pins of the same row. The pins project below board 27 for wiring interconnections and they project above strip 28 to be engaged by the connector assembly of this invention. A ground rail 30 is mounted on board 27 along side strip 28. The ground rail is U-shaped to cooperate with pin 29 and the connector assembly shown in FIG. 2 and with a similar pin and connector assembly (not shown) arranged in a mirror image relationship to the right of FIG. 2.

As FIG. 2 shows, the connector fork that has been referred to so far in this description is combined with a second connector fork in a unitary structure by support 21. The connector fork positioned to the right for engagement with ground rail 30 is connected at a crimp region 33 to the two outside ones of wires 23 and will be called the ground connector fork" when it is specifically referred to. The connector fork positioned to the left in FIG. 2 for engagement with pin 29 is connected at a crimp region 34 to the center one of wires 23. It will ordinarily side walls l2, 13. The tines 35, 36, 37 and 38 are shaped to overhang the front and rear walls 14, and the divider 40 for removably retaining the connector forks in the housing.

FIGS. 3 and 4 show the housing cavity that holds the connector forks and receives the pin 29. In the upper portion of the housing, the cavity is relatively wide for receiving the supports 21. Along inside wall portions 42 and 43 the cavity tapers to a narrow region that is bounded in part by generally parallel surfaces 44 shown in FIG. 3 and 45 shown in FIG. 4.

The Tine Skewing Structure According to this invention, the housing cavity is shaped to skew the tines. A projection 49 on surface 44 skews tines 38 toward sidewall 13 and a diagonally opposite projection 50 on cavity surface 44 skews tines 37 toward sidewall 12. This effect can be seen in FIGS. 3 and 4 where pin 29 has a fixed position. In FIG. 3, the projection 50 is generally ramp shaped and bears against the tine 37b to urge both tines 37a, 37b, to the left with respect to pin 29. Tine 37b makes substantially full electrical contact with pin 29 and tine 37a makes a partial but effective contact with pin 29. FIG. 3 also shows the ramp shape of projection 49 in relation to the cavity surface 44.

FIG. 4 shows the relationship of projection 49 to tines 38a and 38b. Projection 49 is ramp shaped and engages tine 38a to urge both tines 38a and 38b to the right in FIG. 4 toward surface 45. Tine 380 makes substantially full electrical contact with pin 29 and tine 38b makes a partial but effective contact with pin 29.

FIG. 5 shows the skewed relationship of tines 37 and 38. Tine 38a fits closely against projection 49 and tine 37b fits closely against projection 50. A space remains between 38b and cavity surface 45 and between tine 37a and cavity surface 44. This space permits the connector fork to be inserted into the housing and removed and provides for manufacturing tolerances. Because the tines are resillient, the skewing effect produced by projections 49 and 50 causes tine 38b to be urged toward tine 38a and projection 49 and causes tine 37a to be similarly urged toward tine 37b and projection 50. Thus, it is unlikely that tine 37a or 37b would be incorrectly positioned in the open regions between a surface 44 or 45 and the adjacent, non-contact making, side of pin 29.

The housing is also useful for carrying a single connector fork. Projections 49, 50 help to locate the connector fork for a gripping engagement with pin 29.

The advantages of this invention can be better appreciated by recognizing that the drawing shows ideal dimensions that do not illustrate the problems presented by a practical range of manufacturing tolerances. In addition, the pins tend to have rather rounded corners where FIG. 5 shows a square section, and the very thin walls 12, 13 of the housing can be rather easily flexed or otherwise distorted. Thus, except for the pro- 5 jections 49 and 50, a slight change in the dimensions of the drawing and in the centering of pin 29 within the housing cavity could provide space between pin 29 and a cavity surface 44 or 45 into which one of the connector forks could fit. As has already been explained, such a non-gripping electrical contact between the fork connector and the pin is unsatisfactory.

From the description of the preferred embodiment of the invention and the generalizations of this embodiment that has been discussed, those skilled in the art will recognize a wide range of connector assemblies to which this invention applies and appropriate additions and modifications within the spirit of the invention and the scope of the claims.

What is claimed is: v

l. A connector assembly having a housing adapted to fit over a pin having a generally rectangular cross section, said housing having a cavity to ho d up to a predeterrmned number of connector forks in a position for tines on said forks to grip opposite contact making surfaces of the pin, the plurality of tines being wider than the contact making surfaces of the pin,

wherein the improvement comprises,

means mounted on said housing for engaging two diagonally opposite outside ones of said tines and skewing the tines on one of said opposite contact making surfaces of said pin with respect to the tines on the other contact making surface of said pin to maintain said two diagonally opposite ones of said tines in substantially full electrical contact with said contact making surfaces of said pin and to maintain the other two diagonally opposite ones of said outside tines in partial but effective contact with the pin.

2. The assembly of claim 1 in which said skewing means comprises projections from the surfaces of said cavity to engage said two diagonally opposite tines.

3. The assembly of claim 2 in which said cavity is of a size to hold at most two of said connector forks.

4. The assembly of claim 3 in which said housing cavity is open in the region of said other two diagonally opposite tines to provide clearance for sliding the connector forks in the housing during an assembly or disassembly operation.

5. The assembly of claim 4 in which said projections extend partially along the non-contact making sides of said pin for locating said tines with respect to said pin.

6. The assembly of claim 5 in which said projections are ramp shaped for ease of assembly of said connector forks in said cavity.

7. The assembly of claim 6 in which said tines are sufficiently resilient for said tines near said other diagonally opposite edges to be urged by the action of skewing the contact forks toward a position of maximum electrical contact with said pin.

II! l 4' 4 t 

1. A connector assembly having a housing adapted to fit over a pin having a generally rectangular cross section, said housing having a cavity to hold up to a predetermined number of connector forks in a position for tines on said forks to grip opposite contact making surfaces of the pin, the plurality of tines being wider than the contact making surfaces of the pin, wherein the improvement comprises, means mounted on said housing for engaging two diagonally opposite outside ones of said tines and skewing the tines on one of said opposite contact making surfaces of said pin with respect to the tines on the other contact making surface of said pin to maintain said two diagonally opposite ones of said tines in substantially full electrical contact with said contact making surfaces of said pin and to maintain the other two diagonally opposite ones of said outside tines in partial but effective contact with the pin.
 2. The assembly of claim 1 in which said skewing means comprises projections from the surfaces of said cavity to engage said two diagonally opposite tines.
 3. The assembly of claim 2 in which said cavity is of a size to hold at most two of said connector forks.
 4. The assembly of claim 3 in which said housing cavity is open in the region of said other two diagonally opposite tines to provide clearance for sliding the connector forks in the housing during an assembly or disassembly operation.
 5. The assembly of claim 4 in which said projections extend partially along the non-contact making sides of said pin for locating said tines with respect to said pin.
 6. The assembly of claim 5 in which said projections are ramp shaped for ease of assembly of said connector forks in said cavity.
 7. The assembly of claim 6 in which said tines are sufficiently resilient for said tines near said other diagonally opposite edges to be urged by the action of skewing the contact forks toward a position of maximum electrical contact with said pin. 